Scientist Spots Missing Link in his Basement, but is too Sleepy to Catch it

If everything works out right a child in the years between two and ten spends hundreds of hours lying on the floor in her room contemplating childhood, walls, ceilings and whatever clouds float across the horizons of young, brains. Such hours of quiet revelation are important. It is during them when strange creatures sometimes come most clearly into view. As an adult, I am afforded relatively few days during which I have enough time to just lie around staring at the walls or the sky. But several nights ago such an opportunity arose. That is when I saw my first glimpse of the missing link.

I went to work all day, came home, had dinner with my family, got the kids to bed and then and only then remembered I had promised Bora—no last name necessary, benevolent wizard of science blogs—I would write an article about how toilets saved the world, by six AM the next day. I had already worked a dozen hours on the piece. It seemed as though I could get the story finished in an hour or so, but sometimes words and ideas are stubborn. Midnight came and went. So did 1 am, 2 am, and 3 am. At 4 am, I began to have my doubts about whether I would finish, which is when I decided to lie down on the floor and stare at things for a moment. I was giving my mind a break and stretching my body, but I was tired. I probably would have fallen asleep then and there on the floor had what happened next not happened. In an instant, everything can change. He came out of a dark corner of the basement. He had long black legs, a hard, dark body, and two thick mouthparts, of the sort one has nightmares about. A carabid beetle! The beetle high-stepped his way across the computer-lit room. I felt a certain companionship towards the beetle. Like me, he seemed to be searching for something that might or might not be found. I watched him run until he disappeared into the darkness. Then, a few minutes later, he reappeared! He had something white it his mouth, a morsel of success. I could not help but smile. Here were predator and prey in among the wild landscape of couch, desk, and old refrigerator. The ancient passion play of predation was being reenacted, as though just for me.

I watched for a while longer. The beetle did not return, but it did not matter. I was inspired. I finished my article on ecology of toilets. The sun began to rise through the basement windows. My wife and children were waking up. Ruby, the neighbor’s dog was barking. I should have gone back to sleep, if only for a minute, but amid the morning sounds I got to wondering about the beetle. In my searching, I found my story. I could not help wondering what the beetle, in his searching, found.

As I’ve already said, the beetle was carrying some smaller beast, but what kind? I have not seen many prey species in my house. In the relatively small literature on the species inside houses, little is said about who eats who or who eats what.

I can imagine at least two food webs in my house. One starts with my two-year-old son and the food he drops on the floor. Scraps of old macaroni, cheese sticks, and carrots feed scavengers and generalists who, in turn, are fed upon by the predators who, I suppose, are also at the mercy of even more specialized predators or parasites. The other food web begins with the dust-like bits of skin floating around my house (and your house too), skin that feeds microbes but also dust mites that in turn feed even larger mites (leopard mites, I’ve called them elsewhere) and maybe other predators. But little of this is well known and, as my friend Piotr Nasckrecki (author of the amazing new book, Relics) has pointed out, when one tallies an informal list of the species in houses there seem to be far more predators than scavengers and omnivores. So what gives? What do these predators eat? If my basement is a pint-sized Serengeti of many-legged lions, leopards and hyenas, where were the wildebeests or even the zebras? Suddenly, I wished I had stopped the beetle to see what it had killed. In its jaws was the missing link, in the food web, or one of them anyway.

Humans have spent millennia studying predation. Among the first drawings are depictions of the hunt. We are attracted to these sketches, perhaps because we ourselves only recently escaped the constant threat of being eaten. Where predators intersect our lives, we can’t help but to pause and look on. An entire book has been written about a pair of red-tailed hawks who nest in Manhattan. New Yorkers, a tribe largely immune to influence of nature, have taken to these big birds and, I think, the reminder they offer about our place in the nature of things. When these raptors stoop on doves--their wings tucked and their feathers beat back by the wind--they hit their prey so hard the motions of two flying birds become one. We are left, in those moments, to choose with whom we sympathize.

Our sympathies seldom lie with the prey (unless of course it is a poodle and then everything changes...). We imagine ourselves to be at the top of food chain. Being a predator in my basement is noble. Being the animal that finds and eats the old macaroni is not. All the same, where are the prey—those animals being turned, each day, into the bodies of predators? Strange exceptions involving whales and plankton notwithstanding, prey are almost always many-fold more common than their predators. So what is going on in my basement, or your basement, or our houses more generally? This may seem like an idle question. It is not. Consider New York City. In many places, including New York City, the domestic biome is the dominant biome.

Globally, our homes—whether apartments, doublewides or suburban castles—are among the most rapidly expanding habitats on Earth and we don’t seem to know who is eating who within them. There are anecdotes, of course--a spider eating a fly in New Jersey, ants eating bedbugs during the civil war, a cat on youtube who kills roaches. Yet the big picture is fuzzy, all the more so because of how close it is to our daily lives, too near to be quite in focus. This mystery has a resolution. It could be that roaches, dust mites, and, dare I say the word, bed bugs, are far more abundant than they seem. Or maybe the predators sneak outside to feed around the house at night, though that is not what my beetle was doing, nor is it what the spiders beneath our couches, tables and chairs do. They seem to persist for years in their intricate webs, surrounded by eggs.

The way forward is clear. We need to stare at our floors and walls. All around the world, citizen science projects are enlisting kids to go out and collect ants, record butterflies, or even photograph beetles. I think we need something different. We and our children need to stay up late, watching. And so when you finish reading in bed, look around your room. When I finish this article, I'll do the same. Let's listen for the animals moving. They are there, in the fog of darkness, those tiny lions stalking their prey. Watch for their hairy shadows. You could be the next Jane Goodall, but not the one who studies chimps, the other one who sits on the ground and waits for the wild to come to her, one beetle at a time. When the wild does come, when the beasts walk to you or past you on their long fast legs, take notes and pictures, especially if you see the prey. The prey, like ideas, lurk everywhere, unseen but present. There are millions of them in each and every house. I know it. They are breathing invisibly wherever we reside. No matter how modern we become they are with us, living in our midst, where the wild things are. They are, after all, the wild things, whatever they might be.

I challenge everyone to capture the wild prey of their houses, on film. Piotr Naskrecki, Alex Wild, and Derek Sikes, I challenge you in particular to find these missing scenes of nature in our midst. Show me predation. Show me prey. I will be watching too, of course (there will be more deadlines), but I could use help. When photos come in, we can post them here, but I'll also put them up on my wild life site (yourwildlife.org). Photos can be posted here...https://www.flickr.com/groups/wildlifeofhomes/

Whether or not you see the missing links yourself, feel free to perform the additional public natural history service of drawing up the food chain, pyramid or web of a house, as you imagine it. The image can be funny or serious, drawn on the computer or in ancient squid ink. However you do it, it will be one of the first of its kind. So far the food webs of our daily lives haven’t made it into the textbooks. If you design a nice version, it will at least make it onto my group's website, where you can read more about the species around you (www.yourwildlife.org) and around your neighbors too.

The views expressed are those of the author(s) and are not necessarily those of Scientific American.

ABOUT THE AUTHOR(S)

Rob Dunn

Rob Dunn is a biologist at North Carolina State University and a writer whose articles have appeared in Natural History, Smithsonian and National Geographic, among other publications.

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